Patents by Inventor Steven L. Piedmont

Steven L. Piedmont has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8347737
    Abstract: A pressure sensor for measuring a pressure of a fluid in fluid flow path of a fuel cell system is disclosed. The pressure sensor includes a housing provided with a communication path formed between the fluid flow path and an interior of the housing, the communication path having a hydrophobic feature to militate against a formation and an accumulation of an undesired material within the pressure sensor.
    Type: Grant
    Filed: January 10, 2011
    Date of Patent: January 8, 2013
    Assignee: GM Global Technology Operations LLC
    Inventors: Jon P. Owejan, Mark T. Schluentz, Steven L. Piedmont
  • Publication number: 20120174685
    Abstract: A pressure sensor for measuring a pressure of a fluid in fluid flow path of a fuel cell system is disclosed. The pressure sensor includes a housing provided with a communication path formed between the fluid flow path and an interior of the housing, the communication path having a hydrophobic feature to militate against a formation and an accumulation of an undesired material within the pressure sensor.
    Type: Application
    Filed: January 10, 2011
    Publication date: July 12, 2012
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Jon P. Owejan, Mark T. Schluentz, Steven L. Piedmont
  • Patent number: 8133624
    Abstract: A fuel cell system is disclosed including a fuel cell stack and pressure sensors, wherein bypass conduits having flow restriction devices disposed therein are provided for bypassing fluids around the fuel cell stack to militate against the accumulation of moisture in conduits in fluid communication with the pressure sensors.
    Type: Grant
    Filed: April 24, 2008
    Date of Patent: March 13, 2012
    Assignee: GM Global Technology Operations LLC
    Inventors: Daniel J. Darga, Mark T. Schluentz, Steven L. Piedmont
  • Patent number: 7879503
    Abstract: A fuel cell stack including a bypass is provided. The fuel cell stack includes a plurality of electricity generating cells in the known manner. A bypass is included for reducing the water entering the electricity generating cells of the fuel cell stack. The bypass may comprise at least one bypass cell disposed adjacent the first electricity generating cell in the stack. The bypass cell comprises a pair of separator plates defining an anode side and a cathode side. The bypass cell includes a conductive spacer comprising gas diffusion media disposed between the pair of separator plates. The bypass cell preferably blocks the cathode port on the separator plate. In this manner, the cell is inactive and does not produce electricity. The anode port of the cell remains open and an anode feed flows through the bypass to reduce water provided to the first electricity-generating cell. Alternatively or additionally, the cathode port remains open. Further the bypass may be placed before the cell stack itself.
    Type: Grant
    Filed: August 19, 2005
    Date of Patent: February 1, 2011
    Assignee: Gm Global Technology Operations LLC
    Inventors: Charles Mackintosh, Seth Valentine, Sitima R. Fowler, Steven L. Piedmont
  • Publication number: 20090269637
    Abstract: A fuel cell system is disclosed including a fuel cell stack and pressure sensors, wherein bypass conduits having flow restriction devices disposed therein are provided for bypassing fluids around the fuel cell stack to militate against the accumulation of moisture in conduits in fluid communication with the pressure sensors.
    Type: Application
    Filed: April 24, 2008
    Publication date: October 29, 2009
    Inventors: Daniel J. Darga, Mark T. Schluentz, Steven L. Piedmont
  • Patent number: 4741318
    Abstract: A system and method of controlling the purge rate of a fuel vapor collection canister of an internal combustion engine in which the purge flow rate is variably controlled to a maximum rate that is established by the fuel control system based on its ability to maintain a desired air/fuel ratio.
    Type: Grant
    Filed: August 22, 1986
    Date of Patent: May 3, 1988
    Assignee: General Motors Corporation
    Inventors: Jerry W. Kortge, Steven L. Piedmont